The paper, "Review of Fused Single-Mode Coupler Technology," C. M. Ragdale et al., Proceedings of SPIE--The International Society for Optical Engineering, Fiber Optic Coupler, Connectors, and Splice Technology, Vol. 479, pp. 2-8, May 1-2, 1984, incorporated herein by reference, is an example of the prior art describing optical couplers. Such couplers typically include two optical input ports and two optical output ports, each port connected to an optical fiber. Light energy entering either of the two input ports is divided in any of various prescribed fashions by the optical coupler and transmitted through either or both of the two output ports. When the optical couplers are made, it is customary to include optical fibers, sometimes known as "pigtails," connected to the two input and the two output ports.
The copending application of Holland, Serial No. 08/143,670, filed Nov. 1, 1993, incorporated herein by reference, describes a method for routing the optical fibers extending from a device. The apparatus described picks up the optical fiber, winds it on a reel and then routes the fiber on the surface of a substrate that has been covered with pressure-sensitive adhesive. After the fiber has been routed, the fibers are encapsulated with a thermoplastic sheet to stabilize them and to protect them from the environment, from the effects of rough handling, etc. The encapsulated fibers typically constitute an optical backplane used to interconnect electrical or optical subsystems. It would be desirable to adapt this technique to the routing of optical fibers extending from opposite ends of optical couplers in such a manner that the couplers and fibers are made part of a unitary optical backplane package in which the optical fibers extending from both ends of each coupler are routed in a desired manner, are encapsulated and protected from the environment, and are connectable to other apparatus.